The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Reloading Trim Length?Go | New | Find | Notify | Tools | Reply | |
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| one of us |
Been thinking. I getting powder burns (black residue) on the necks of my reloads (not on factory ammo). If I don't trim to what the book says, say 0.05 longer, would that help? 7mm-08, Max. case length: 2.035", trim-to length: 2.025". Change it to trim length of 2.030". What do you think? Bulldog... | ||
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| <Gary Rihn> |
Can't hurt to try. But there's lots of reasons that you could be getting smudges on the neck. I doubt that the case length is the culprit. | ||
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| one of us |
BTW, I forgot to mention that it shows up on my 223 also. I did notice that a friend of mine had the same on his 280 with factory rds. All guns shoot great and there is no other problems that I notice. The brass cleans up nice after its tumbled. All brass is once shot factory. Bulldog... | |||
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one of us |
Your thinking is courting with disaster. First of all, most chambers have about a .020" leeway for length of neck. That's as much as .030" over trim length. Sinclair sells some plugs to enable you to determine the true max in your chamber. You can also check this on your own with a donut cut from a neck, place on a reversed bullet and chambering in a case with the neck cut off. You can usually safely exceed the max length considerably. This is to prevent dummies who don't regularly check and trim their cases, from blowing up their guns. However, regardless of what you do, the soot on your neck is quite normal. Your factory rounds may also show this. You'll never be able to prevent it. You'll be safe even if you hit the maximum specified. Just don't mess with it. Your observations are quite normal. [This message has been edited by Bob338 (edited 09-28-2001).] | |||
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| one of us |
Bob, you solved that problem, or what there was of it. Thanks for the info. I'm not going to worry about it anymore, unless the soot goes beyond the neck. Thanks also Gary. Bulldog... | |||
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| one of us |
Bulldog, If you want the soot off the neck then go to a progressively faster powder and that will cure the problem... With a powder thats is a little slow the neck doesn't expand fast enough to stop a little blowback, the slower powder is not as effecient as the faster powder, even though the slower powder may give you better velocity in some instances.. I'm not sure I agree with Bob338 as to chamber necks being long for safty, if that were the case then there would be no need for trimming and throat erosion would be pronounced post haste...I know in my rifles that I build that is not the case and I have not seen that in Factory rifles that I have cerrosafed. Also reamers are cut to Saami specs and that doesn't allow for long necked chambers..Now throats are a different story but that doesn't apply to trimming... ------------------ | |||
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| one of us |
I've read the other posts on the soot problem. Even asked it somewhere. I see it not posing a problem, unless it changes to beyond the neck area. The guns that I use are new, except the 788. I am new to reloading, so I wasn't sure if it was typical or something to be worried about. I just had a thought that maybe it could be related to trim length. The burn rate makes sense. So far I used IMR4350, Re19, & Varget powders, Rem. & Fed. brass on the 7mm-08 and Win. brass on the 223. All have this soot showing up, some loads more, some loads less. Sometimes it goes 1/2 way down the neck and sometime the whole neck is black. My groups are great, and I've not found any pressure signs so far on all my loads that I've tested. I do know factory ammo has never before done this, so I figure it could be in the prepping of the cases or as pointed out the burn rate of the powder. Maybe my trimmer does not trim square, could that be a cause? Maybe I deburr and chamfer to hard, and cause a problem there. It could be I don't clean the insides of the neck well enough and the crap from the Lyman corncob media is causing a problem. Who knows, but one day I'll find out and let everyone know. Thanks for the responses. Bulldog... [This message has been edited by bulldog (edited 09-29-2001).] | |||
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| one of us |
It shows up on test batches, min. charge to max. charge. Soot on neck on all. Amount doesn't change much between charges. There is no pattern to it per grains used. Got a burn rate chart and going to try a faster powder next. The powders that I have used are at the very bottom of the chart. Bulldog... | |||
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| one of us |
Bulldog, bulldog, Bulldog, Son, I told you what was causing the problem, either up the load to near max or go a faster powder...  ------------------ | |||
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| one of us |
Atkinson, Atkinson, Atkinson, What do you mean up the load to max.? My last post stated that I started at the min. charge and I increased to max. charge. All this in one grain increments. Do you want me to go beyond what the manual says??? The soot shows up on ALL of my rounds that I've shot. That includes the min. charge rounds to the max. charge rounds (with Re19, max. was a compressed charge). I also stated in my last post just before yours, that my next change would be to go to a faster powder... BTW, I'm probably old enough to be you father Bulldog... | |||
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| one of us |
I'll say it one more time, then you and Atkinson can keep on being pen pals. Soot on the neck is NORMAL. You'll never prevent it except possibly in a tight necked benchrest rifle. Soot is NOT normal beyond the shoulder. If you have it there then you need to look at your load which probably needs to be more potent, or at your sizing of the body of your brass and setting the shoulder back too far. You DON'T have a problem as near as I can tell and you'll never prevent the soot on the neck. | |||
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| one of us |
I agree Bob. Lets end it here. SOOT IS NORMAL! I LOVE SOOT!  Bulldog... | |||
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| one of us |
Bulldog,Bulldog, If your old enough to be my father, your talking from the grave, folks don't live that long... I understood your post to mean that you didn't get soot from factory loads! There are powders that burn faster and have an expansion ratio that is fast enough to stop sooting necks on any caliber. I thought this was a problem you wanted to solve by your first post and was simply trying to solve it for you as you requested, however it appears that it is not a problem after all, so I won't post further argueably good advise... ------------------ | |||
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| one of us |
Mr. Atkinson, I have appreciated your post and consider them good advice. Being a newbie to this reloading, and reading everything I can get my hands on, I sometimes have to ask questions that to some are trivial, but to me are very important to reloading. I have found this forum to be an excellent place to read up on advice and suggestions. I use the search first and if the answers do not help, I post my problem. Concerning this post, I had read somewhere else that some don't trim as short as recommended in the manuals. After checking the brass length on unfired ammo from the major manufacturers I noticed the brass length was longer than the recommended trim length , but not past the recommended max. case length. Being curious, I hope to get feedback on this to explore that possibility for the sooty neck problems. I hope, in the future, you will help me with my newbie questions as I consider your advice and advice from others good advice. If I see that there is a conflict with the different advice that I receive, then I will hold off with proceeding any further with the problem until I can ascertain the correct response to the problem. I hope that my humor will not in any way, stop you from helping myself or others in their endeavor in reloading. To learn one must read, listen, and ask questions. Good Reloading... Bulldog | |||
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| one of us |
quote: I suspect that you'll get different amounts of case dirtying with different powders. For my part, I found that Varget makes the outside of cases dirtier than any other powder I've ever used, especially in loads that are not full power. | |||
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| <PowderBurns> |
Couple other things might be causing soot. The neck expander in the sizing die may be a bit large. This affects neck tension. Neck tension affects how the powder ignites in the case before the bullet clears the brass. You can fuss with the neck expander with a bit of steel wool and reduce its diameter. But you're messing with some fine tolerances here. Easy does it. Faster powder, stiffer load . . . That will seal the neck of the brass -- sometimes. I regularly trim my brass to the max. OAL per SAMMI spec. But I've also measured the length of the neck in the chamber, bullet ogive. This is rocket science, not touchy/feely estimation. Necks get brittle from shooting and reloading. I anneal the neck after five loads in .223. Larger calibers may need it more often. Once fired brass should need neither trimming nor annealing -- unless it's that military reload stuff where the brass may have been anywhere before it got to your press. But . . . soot ain't no big deal. Worry about stuff like large flakes of unburned powder coming out of the muzzle and setting fire to the grass on the range.
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| <sure-shot> |
Bulldog, just buy the plugs from Sinclair and use em, it will save you from trimming your brass unnecessarily or too often like Bob338 suggested. Don't worry about that soot I see it on alot of my casings, it will wipe off easy if you keep some krazy cloth handy. Also don't get too riled if "ole Ray" leans on ya, he's a good fella with alot of heart plus he's "right" about 95% of the time I figure. sure-shot | ||
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